Display device and method for fabricating the same

Abstract

A display device includes: a substrate; a first electrode on the substrate; a light emitting layer on the first electrode; a pixel defining layer on the light emitting layer; and a second electrode on the light emitting layer. First and second opposite sides of the light emitting layer are located on the pixel defining layer, and have straight line shapes that are inclined at an angle with respect to an upper surface of the pixel defining layer.

What is claimed is: 
     
         1 . A display device comprising:
 a substrate;   a first electrode on the substrate;   a light emitting layer on the first electrode;   a pixel defining layer on the light emitting layer; and   a second electrode on the light emitting layer,   wherein first and second opposite sides of the light emitting layer are located on the pixel defining layer, and have straight line shapes that are inclined at an angle with respect to an upper surface of the pixel defining layer.   
     
     
         2 . The display device of  claim 1 , wherein an angle between the upper surface of the pixel defining layer and the first side of the light emitting layer is greater than 60° and smaller than or equal to 90°, and
 wherein an angle between the upper surface of the pixel defining layer and the second side of the light emitting layer is greater than 60° and smaller than or equal to 90°. 
 
     
     
         3 . The display device of  claim 1 , wherein a distance between the first side of the light emitting layer and the second side of the light emitting layer gradually decreases in a direction away from the pixel defining layer. 
     
     
         4 . The display device of  claim 1 , further comprising a first functional layer between the first electrode and the light emitting layer. 
     
     
         5 . The display device of  claim 4 , wherein first and second opposite sides of the first functional layer are located on the pixel defining layer, and have straight line shapes inclined at an angle with respect to the upper surface of the pixel defining layer. 
     
     
         6 . The display device of  claim 5 , wherein an angle between the upper surface of the pixel defining layer and the first side of the first functional layer is greater than 60° and smaller than or equal to 90°, and
 wherein an angle between the upper surface of the pixel defining layer and the second side of the first functional layer is greater than 60° and smaller than or equal to 90°. 
 
     
     
         7 . The display device of  claim 5 , wherein a distance between the first side of the first functional layer and the second side of the first functional layer gradually decreases in a direction away from the pixel defining layer. 
     
     
         8 . The display device of  claim 4 , wherein the first functional layer comprises:
 a hole injection layer on the first electrode; and   a hole transport layer on the hole injection layer.   
     
     
         9 . The display device of  claim 1 , further comprising a second functional layer between the light emitting layer and the second electrode. 
     
     
         10 . The display device of  claim 9 , wherein first and second opposite sides of the second functional layer are located on the pixel defining layer, and
 wherein the first and second sides of the second functional layer have straight line shapes inclined at an angle with respect to the upper surface of the pixel defining layer.   
     
     
         11 . The display device of  claim 10 , wherein an angle between the upper surface of the pixel defining layer and the first side of the second functional layer is greater than 60° and smaller than or equal to 90°, and
 wherein an angle between the upper surface of the pixel defining layer and the second side of the second functional layer is greater than 60° and smaller than or equal to 90°. 
 
     
     
         12 . The display device of  claim 10 , wherein a distance between the first side of the second functional layer and the second side of the second functional layer gradually decreases in a direction away from the pixel defining layer. 
     
     
         13 . The display device of  claim 9 , wherein the second functional layer comprises a buffer layer on the light emitting layer. 
     
     
         14 . The display device of  claim 9 , further comprising a common buffer layer between the second functional layer and the second electrode. 
     
     
         15 . The display device of  claim 14 , further comprising a first functional layer between the first electrode and the light emitting layer,
 wherein the common buffer layer is located on the first and second sides of the light emitting layer, first and second sides of the first functional layer, and first and second sides of the second functional layer.   
     
     
         16 . The display device of  claim 14 , further comprising an electron transport layer between the common buffer layer and the second electrode. 
     
     
         17 . The display device of  claim 16 , wherein, in a plan view, the electron transport layer is located on the common buffer layer to surround the light emitting layer. 
     
     
         18 . The display device of  claim 1 , further comprising an encapsulation layer on the second electrode. 
     
     
         19 . The display device of  claim 1 , wherein the pixel defining layer comprises an inorganic layer. 
     
     
         20 . A method for fabricating a display device, the method comprising:
 disposing a first electrode on a substrate;   disposing a pixel defining layer on the first electrode;   disposing a first functional layer, a light emitting layer, a second functional layer, and a sacrificial layer on an entire surface of the substrate including the pixel defining layer;   disposing a photoresist pattern on the sacrificial layer to overlap with the first electrode;   etching the first functional layer, the light emitting layer, the second functional layer, and the sacrificial layer by using the photoresist pattern as a mask so that the first functional layer, the light emitting layer, the second functional layer, and the sacrificial layer are disposed between the first electrode and the photoresist pattern;   removing the photoresist pattern; and   removing the etched sacrificial layer.   
     
     
         21 . The method of  claim 20 , further comprising cleaning the substrate including the etched first functional layer, the etched light emitting layer, and the etched second functional layer. 
     
     
         22 . The method of  claim 21 , further comprising:
 disposing the cleaned substrate in a vacuum chamber; and   baking the substrate in the vacuum chamber.   
     
     
         23 . The method of  claim 22 , further comprising disposing a common buffer layer on the second functional layer of the baked substrate in the vacuum chamber. 
     
     
         24 . The method of  claim 23 , further comprising disposing an electron transport layer on the common buffer layer in the vacuum chamber. 
     
     
         25 . The method of  claim 24 , further comprising disposing a second electrode on the electron transport layer in the vacuum chamber. 
     
     
         26 . The method of  claim 20 , wherein, in the etching of the first functional layer, the light emitting layer, the second functional layer, and the sacrificial layer by using the photoresist pattern as a mask, the first functional layer, the light emitting layer, the second functional layer, and the sacrificial layer are etched by dry etching. 
     
     
         27 . The method of  claim 20 , wherein, in the removing of the etched sacrificial layer, the etched sacrificial layer is removed by an etchant. 
     
     
         28 . The method of  claim 20 , wherein the sacrificial layer comprises at least one of aluminum or silver.